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	<head>
		<title>Multiple animated skinned meshes</title>
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	<body>
		<div id="info">
			This demo shows the usage of <strong>SkeletonUtils.clone()</strong> and how to setup a shared skeleton.<br/>
			Soldier model from <a href="https://www.mixamo.com" target="_blank" rel="noopener">https://www.mixamo.com</a>.
		</div>

		<script type="importmap">
			{
				"imports": {
					"three": "../build/three.module.js",
					"three/addons/": "./jsm/"
				}
			}
		</script>

		<script type="module">

			import * as THREE from 'three';

			import { GLTFLoader } from 'three/addons/loaders/GLTFLoader.js';
			import * as SkeletonUtils from 'three/addons/utils/SkeletonUtils.js';
			import { GUI } from 'three/addons/libs/lil-gui.module.min.js';

			let camera, scene, renderer, clock;
			let model, animations;

			const mixers = [], objects = [];

			const params = {
				sharedSkeleton: false
			};

			init();

			function init() {

				camera = new THREE.PerspectiveCamera( 45, window.innerWidth / window.innerHeight, 1, 1000 );
				camera.position.set( 2, 3, - 6 );
				camera.lookAt( 0, 1, 0 );

				clock = new THREE.Clock();

				scene = new THREE.Scene();
				scene.background = new THREE.Color( 0xa0a0a0 );
				scene.fog = new THREE.Fog( 0xa0a0a0, 10, 50 );

				const hemiLight = new THREE.HemisphereLight( 0xffffff, 0x8d8d8d, 3 );
				hemiLight.position.set( 0, 20, 0 );
				scene.add( hemiLight );

				const dirLight = new THREE.DirectionalLight( 0xffffff, 3 );
				dirLight.position.set( - 3, 10, - 10 );
				dirLight.castShadow = true;
				dirLight.shadow.camera.top = 4;
				dirLight.shadow.camera.bottom = - 4;
				dirLight.shadow.camera.left = - 4;
				dirLight.shadow.camera.right = 4;
				dirLight.shadow.camera.near = 0.1;
				dirLight.shadow.camera.far = 40;
				scene.add( dirLight );

				// scene.add( new THREE.CameraHelper( dirLight.shadow.camera ) );

				// ground

				const mesh = new THREE.Mesh( new THREE.PlaneGeometry( 200, 200 ), new THREE.MeshPhongMaterial( { color: 0xcbcbcb, depthWrite: false } ) );
				mesh.rotation.x = - Math.PI / 2;
				mesh.receiveShadow = true;
				scene.add( mesh );

				const loader = new GLTFLoader();
				loader.load( 'models/gltf/Soldier.glb', function ( gltf ) {

					model = gltf.scene;
					animations = gltf.animations;

					model.traverse( function ( object ) {

						if ( object.isMesh ) object.castShadow = true;

					} );

					setupDefaultScene();

				} );

				renderer = new THREE.WebGLRenderer( { antialias: true } );
				renderer.setPixelRatio( window.devicePixelRatio );
				renderer.setSize( window.innerWidth, window.innerHeight );
				renderer.setAnimationLoop( animate );
				renderer.shadowMap.enabled = true;
				document.body.appendChild( renderer.domElement );

				window.addEventListener( 'resize', onWindowResize );

				const gui = new GUI();

				gui.add( params, 'sharedSkeleton' ).onChange( function () {

					clearScene();
			
					if ( params.sharedSkeleton === true ) {

						setupSharedSkeletonScene();

					} else {

						setupDefaultScene();

					}
			
				} );
				gui.open();

			}

			function clearScene() {

				for ( const mixer of mixers ) {

					mixer.stopAllAction();

				}

				mixers.length = 0;

				//

				for ( const object of objects ) {

					scene.remove( object );

					scene.traverse( function ( child ) {

						if ( child.isSkinnedMesh ) child.skeleton.dispose();

					} );

				}

			}

			function setupDefaultScene() {

				// three cloned models with independent skeletons.
				// each model can have its own animation state

				const model1 = SkeletonUtils.clone( model );
				const model2 = SkeletonUtils.clone( model );
				const model3 = SkeletonUtils.clone( model );

				model1.position.x = - 2;
				model2.position.x = 0;
				model3.position.x = 2;

				const mixer1 = new THREE.AnimationMixer( model1 );
				const mixer2 = new THREE.AnimationMixer( model2 );
				const mixer3 = new THREE.AnimationMixer( model3 );

				mixer1.clipAction( animations[ 0 ] ).play(); // idle
				mixer2.clipAction( animations[ 1 ] ).play(); // run
				mixer3.clipAction( animations[ 3 ] ).play(); // walk

				scene.add( model1, model2, model3 );
			
				objects.push( model1, model2, model3 );
				mixers.push( mixer1, mixer2, mixer3 );

			}

			function setupSharedSkeletonScene() {

				// three cloned models with a single shared skeleton.
				// all models share the same animation state

				const sharedModel = SkeletonUtils.clone( model );
				const shareSkinnedMesh = sharedModel.getObjectByName( 'vanguard_Mesh' );
				const sharedSkeleton = shareSkinnedMesh.skeleton;
				const sharedParentBone = sharedModel.getObjectByName( 'mixamorigHips' );
				scene.add( sharedParentBone ); // the bones need to be in the scene for the animation to work

				const model1 = shareSkinnedMesh.clone();
				const model2 = shareSkinnedMesh.clone();
				const model3 = shareSkinnedMesh.clone();

				model1.bindMode = THREE.DetachedBindMode;
				model2.bindMode = THREE.DetachedBindMode;
				model3.bindMode = THREE.DetachedBindMode;

				const identity = new THREE.Matrix4();

				model1.bind( sharedSkeleton, identity );
				model2.bind( sharedSkeleton, identity );
				model3.bind( sharedSkeleton, identity );

				model1.position.x = - 2;
				model2.position.x = 0;
				model3.position.x = 2;

				// apply transformation from the glTF asset

				model1.scale.setScalar( 0.01 );
				model1.rotation.x = - Math.PI * 0.5;
				model2.scale.setScalar( 0.01 );
				model2.rotation.x = - Math.PI * 0.5;
				model3.scale.setScalar( 0.01 );
				model3.rotation.x = - Math.PI * 0.5;

				//

				const mixer = new THREE.AnimationMixer( sharedParentBone );
				mixer.clipAction( animations[ 1 ] ).play();

				scene.add( sharedParentBone, model1, model2, model3 );
			
				objects.push( sharedParentBone, model1, model2, model3 );
				mixers.push( mixer );

			}

			function onWindowResize() {

				camera.aspect = window.innerWidth / window.innerHeight;
				camera.updateProjectionMatrix();

				renderer.setSize( window.innerWidth, window.innerHeight );

			}

			function animate() {

				const delta = clock.getDelta();

				for ( const mixer of mixers ) mixer.update( delta );

				renderer.render( scene, camera );

			}

		</script>

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